Normally when a layer has a mask and the layer is moved, the mask moves with it, however, for Particle Simulator layers, the mask doesn't move with it.
Are you moving the Layer, in the Transform controls, or are you moving the Emitter, in its Shape properties?
I'm moving the layer. I initially saw this with the layer parented to another. The layer and it's particles moved as expected, but the mask didn't. I then manually moved the layer using it's handles and got the same behavior.
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